THERMAL DEGRADATION CHEMISTRY OF LIPIDS: AN AGEING STUDY ON EVOO SAMPLES BY MEANS OF GAS AND LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY TECHNIQUES

Artificial ageing tests can provide key elements to study the formation of characteristic degradation compounds and better address the origin of organic archaeological remains, such as animal fats and plant oils resulting partially or totally altered over time1. In the present research, in-lab thermal-oxidative treatments have been carried out on extra-virgin olive oils (EVOOs), traditionally used in Mediterranean ancient societies, for the purpose of simulating the natural degradation of the lipid matter. In order to obtain meaningful data, several monocultivars of EVOO samples from different Italian regions (Sicily, Tuscany, Apulia, Lazio, Liguria) and Spain, were selected. The ageing of lipids was performed at 120°C for three weeks2. Subsequently, thermal degradation products such as medium- and long-chain fatty acids, (α,ω)-dicarboxylic acids, ketons, lactones, and esters were investigated by using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID) techniques. About the identity of intact lipids, including oxidized lipid species, non-aqueous reversed phase high-performance liquid chromatography (RP-HPLC) coupled to APCI mass spectrometry. The analytical methodologies here proposed, can be helpful in archaeological contexts, to identify specific “archaeological biomarkers” and unveil crucial hints about the daily life of ancient societies. References: 1. Irto, A., … & Cardiano, P., Molecules 27 (2022) 3451 2. Colombini, M. P., … & Ribechini, E. Journal of Mass Spectrometry 40 (2005) 890–898. Acknowledgements: The authors acknowledge Merck Life Science and Shimadzu Corporations for the continuous support.